Mladen Mandić was born and lives with his family in Rijeka. He graduated from the Faculty of Maritime Studies in Rijeka, where he earned the title of Graduate Engineer for Maritime Transport, Nautical.

He completed his internship on Croatia Linea ships. He began sailing on Lošinjska plovidba ships, where he served as a second officer of the deck. In 1989, he took the exam for a long-distance captain in accordance with the Convention on the Qualifications of Seafarers STCW II/2. During 1990, he continued his career in the Rijeka Port Authority, as a senior technical officer for maritime transport, and later as the commander of the SAR ship "Draga", with responsibilities for search and rescue operations and safety at sea.

During 1998, he was appointed to the position of navigation safety inspector, and then assigned to the position of senior nautical inspector in the Rijeka Port Authority.
In 2003, he was particularly noted in an official letter from the American Bureau of Shipping - Rijeka for the inspections carried out that enabled navigation safety and environmental protection. During 2004, he was promoted to the rank of foreign ship safety controller (senior PSC) in the Rijeka Port Authority. In 2007, he was appointed Head of the Inspection Department at LK Rijeka, and at the end of 2010, he was appointed Head of the Inspection Department at the Inspection Department of the Ministry of Maritime Affairs.

In this position, he performs the tasks of coordination and organization of inspection work in maritime inspection, inland navigation, including inspection work of domestic and foreign ships, other sailing vessels, inspection and administrative supervision of maritime property and technical inspections of the Ministry's vessels.

In the position of Head of Department, he coordinates the work of the inspection departments in eight port authorities with the aim of supervising the implementation of inspection procedures for foreign ships and their registration in national and European databases of enforcement supervision for domestic vessels and maritime safety. He is also responsible for supervision, training and authorization for PSCO duties. Coordination is carried out through the provision of instructions and guidelines for domestic vessels. guidelines for foreign ships in accordance with the Paris Memorandum of Understanding (PMOU) procedures.

As part of the quality system, he conducts regular annual assessments of regional offices and proposes changes to existing or the development of new procedures and instructions related to inspection supervision. In addition to the above tasks, he is also engaged in numerous serious investigations of maritime accidents in the Republic of Croatia, and performs audits of recognized ship and port safety organizations and recognized organizations for the statutory certification of ships flying the Croatian flag.

He is involved in solving the problem of piracy and has been involved from the very beginning in the development of a by-law that addresses the issue of engaging armed escorts on ships flying the Croatian flag, all for the purpose of protecting Croatian seafarers.

In the accession negotiations with the European Union, he actively participates in fulfilling the criteria set in Chapter 14. Transport Policy, which referred to the maximum permitted percentage of 5% of stops of Croatian-flagged ships in the ports of the Paris Memorandum member states. He prepared comparative reviews of European maritime regulations with national regulations, all during the process of accession of the Republic of Croatia to the EU.

In order to improve the status of Croatian-flagged ships in the ports of the Paris Memorandum, an Action Plan was adopted, the implementation of which he was personally responsible for. The most important success is the fact that the Croatian flag, based on the good results of inspections in the ports of the Paris Memorandum countries in 2009, was moved from the grey to the white list of the Paris Memorandum. In addition to the above, in recent years he has also been an analyst for the International Maritime Organization (IMO) for maritime accidents of ships.
He is also an auditor for the International Maritime Organization (IMO) in the supervision of state maritime administrations of IMO member states (IMSAS).

He is the contact person in Croatia for missions under the EMSA PSC Directive, the Port Safety Directive, the Sulphur Directive, the Bulk Carriers Safety Operations Directive, and the Croatian representative in the Maritime Security of Ports and Ships (MARSEC) Committee.

After passing the exam at the European Commission, he was authorized to perform special assessments of EU member states as a national inspector, regarding the security of ships and ports.
He is the President of the Commission for the Investigation of Major Maritime Accidents of Ships, the Commission for the Drafting of the Ship and Port Security Act, and the Commission for Determining the Minimum Number of Crew Members on High-Speed ​​Passenger Craft.

He is a member of the Commission for Issuing the Operating Permit for the LNG Terminal in Omišalj in the area of ​​the safety of navigation of the LNG ship LNG Croatia. He is the president/member of the committee for approving port security assessments and plans, a member of the Committee for the Supervision of Recognized Organizations for the Development of Port Security Plans and Assessments, a member of the Committee for the Supervision of Recognized Organizations for the Supervision of the Statutory Certification of Croatian Ships, and a member of the Expert Committee for the Evaluation of the Statutory Rules of the Croatian Register of Shipping.

As a member of the working group, he participated in the drafting of laws and bylaws relating to navigation safety.

As part of his professional development, he participated in special international seminars organized by the Paris Memorandum, the Maritime Safety Agency (EMSA) and the International Maritime Organization (IMO), the International Labor Organization (ILO) and obtained the appropriate certificates. He successfully completed the training course for auditors for the MLC 2006 Convention in 2009 for lead auditors of quality systems organized by Bureau Vertitas, and the course for auditors of ISO 9001:2000 standards, Lloyd's Register EMEA, and then the internal audit of the Ministry, in accordance with the Quality Management System (QMS).

I am a Safety Management System (ISM) assessor certified by the European Maritime Safety Agency. I am responsible for implementing the requirements of the Sulphur Directive relating to the monitoring of sulphur analyses in marine fuel.

I am a member of the team of the national committee for the implementation of Regulation (EU) 2015/757 on the monitoring, reporting and verification of carbon dioxide emissions from maritime transport.